Problem: Umaima eats at a restaurant and the cost of her meal is $\$39.00$. She would like to leave a $10\%$ tip. What is her total bill including tip?
The tip amount is equal to $10\% \times \$39.00$ To calculate a $10\%$ tip, move the decimal point in $\$39.00$ one place to the left. $10\%$ $\times \$39.00$ $\$3.90$ The cost of the meal plus the amount of the tip will equal the total bill amount. $\$39.00 + \$3.90 = $ $\$42.90$ The total cost of the bill is $\$42.90$.